const raf = window.requestAnimationFrame
  || window.webkitRequestAnimationFrame
  || window.mozRequestAnimationFrame
  || window.msRequestAnimationFrame
  || (cb) => (window.setTimeout(cb, 16));

const caf = window.cancelAnimationFrame
  || window.webkitCancelAnimationFrame
  || window.mozCancelAnimationFrame
  || window.msCancelAnimationFrame
  || (id) => (window.clearTimeout(id));